Thursday, 28 March 2013

A study of
visual intervention, to improve reading performance (phonological processing) of a young man originally
identified having congenital occulomotor apraxia (COA).COA interferes with
visual search mechanisms by restricting the formation of saccadic eye movement,
He was then identified as being Dyspraxic and later as he entered Higher
education he was assessed for dyslexia and was identified as dyslexic.

This
intervention took about 1 hour and application of the findings appears to give
rise to a measurable increase in phonological processing speed of 21%...

The testing
included recording and measurement of his eye movements, which are subliminal
at different stages.

The control of
saccades and fixations are managed by the cerebellum in response to visual
processing data and in turn feedback to the edge detection data which is a
product of the controlled saccades and fixations. This can be considered in the
context of the work on the relationship between cerebellum functioning and
dyslexia as centred in the UK at the University of Sheffield led by Nicholson
and Fawcett. It can also be considered in the context of the ideas on
magnocellular deficit and dyslexia developed in UK by John Stein et al at Oxford
with its ideas on binocular instability which is considered to be dependent on
cerebellar function.

This week I had the privilege of working with a
young man (‘A’ )who was diagnosed in his first year of life as having ‘Cogan’s occulomotor
apraxia’ ( Google it for more information).

This is a condition which is congenital and is
linked with the initiation of saccades; the rapid eye movements which redirect
the eyes to new objects of attention. In the graphs on eye movement in previous
blogs these are the vertical lines on the graph as the eyes move from one word
to the next...Or the end of one line to the beginning of the next line.

It is not that the eyes cannot do these movements;
it is that there appears to be a fault in the mechanism which means that they
sometimes do and sometimes do not occur.

When using a binocular eyetracker with many
dyslexic adults, it is quite common for one of the eyes not to saccade when reading in a
default computer screen environment.

When A was young he was diagnosed as being Dyspraxic, which is defined below.

Developmental dyspraxia is an impairment or
immaturity of the organisation of movement. It is an immaturity in the way that
the brain processes information, which results in messages not being properly
or fully transmitted. The term dyspraxia comes from the word praxis, which
means 'doing, acting'. Dyspraxia affects the planning of what to do and how to
do it. It is associated with problems of perception, language and thought.

A typically broad definition, but it was the origin, in a
way, of a great deal of research into Dyslexia
at Sheffield University. Rod
Nicholson and Angela Fawcett’s work showed a statistical relationship between
muscle tone management and the reading difficulties associated with Dyslexia.
This led to intervention work concerned with attempts to train the Cerebellum, which is the brain’s centre for
muscle tone management and coordination.
At one extreme it led to the throwing bean bags in the air, wobble
boards, to try and remediate ‘the problem’.
It also led to the overlap in the protocols for the identification of people
with dyslexia and dyspraxia and much confusion.

Children with COA need a proactive interaction to
mitigate the effects, such as speech therapy and hand eye coordination
excercises. There are strategies which the person develops to initiate
saccades, such as head thrust. Brief sideways jerking of the head) As such with
appropriate support the effects of the apraxia become less and less disabling
as the person goes through their second and third decade.

In the case of A, a remaining issue is his dyslexic
characteristic. My task was to investigate what was really happening visually
and to find out if his reading performance (phonological processing output!)
could be improvedby adjusting the
visual processing input.

Stage
1

Is
there any history of ophthalmic problems?

Visits to opticians suggest that there are no focussing problems
that can be dealt with by ophthalmic intervention. .. Vision is normal. A relatively quick check by myself confirmed
this to be the case.

His job is that of a graphic artist. Precise vision is
needed for this. An example of his work is
given below. (Google Jakgibberish for more examples)

Stage
2.

Find
out about his eye movement management in non reading activities.

The graph below shows A’s eye movements during normal
visual activity; looking around the room we were sitting in...

Normally you would expect the two eye traces to be
matched with distinct, synchronised saccades and fixations. The left eye (the red line) does show a few
saccades, I can pick out six by the right eye (blue line). There are no clear
fixations by the right eye and the right eye goes into a nystagmus occasionally
which interrupts the work of the left eye, pulling it sideways.

Head movements would show up as a sloping
graph, but if both eyes were ‘linked together normally the angle of the slope
would be the same for both eyes. This is not happening here.

Stage
3... Finding out what happens in default reading conditions, the default is a
default (12) font with a white background.

A’s left eye, is moving in a rational way typical of many
readers with clear saccades and fixations, but with many regressions . His
right eye meanwhile, has been turned in towards his nose (to the left) and is
no longer looking towards the text. For his right eye there are no clear
saccades except at the ends of lines.

The rest of the time, the movements of his ‘reading left
eye’ are not influencing/ controlling his right eye. Although in the third and
fourth line, the gradual upward movement during each line suggests that there
is some linkage. You can see three
bursts of nystagmus type activity as well.

We can conclude here that there is no initiation of
saccades, no ‘visual search’, no attention originating, fixations associated
with the right eye, which is a functioning eye.
A decision has been made by his visual system to suppress it! In
biological terms this implies that he is getting better visual data, by using visual
data from only one eye; his left onewhatever the visual activity.

Stage
4. Get a measurement of reading performance.

Using the same Oral reading fluency test that has been
used with over 12,000 adults, A read off a computer screen with a font 12 and
‘white background’

Default Oral reading fluency…….105 wpm

The reading style was stocatal; individual words were
being read in syllables; limited blending.

The mean reading speed for this text by dyslexic
undergraduates is 138 wpm. For non dyslexic undergraduates it is 184 wpm. I can quote Standard deviations but not here.

At the conclusion we will measure Oral reading fluency (a
measure of phonological processing) with an equivalent text, using whatever
optimal settings we identify.

Stage
5..Find out if font size influences reading performance.

This was
undertaken binocularly. The data was unclear. There was a hint that a larger
font than default 12 might be useful and it was decided to use

font 16 point for the next stage.

For
many dyslexic people there is a clear mathematical relationship between font
size and reading performance. See the other posts on this blog.

At this point it became clear that testing A binocularly
was going to be too stressful. The
screen optimisation continued monocularly using only his ‘good’ left eye.
His right eye was covered. This meant that it would still move dependent only
on visual data collected by his left eye,

This was using a font 16 and the following background screen settings.

Oral
reading performance…..127 wpm.

In addition the reading ‘style’ was more fluent, whole
word enunciation now being with a clearly prosodic component.

This is a 21% measurable increase in
performance.

I
have not yet found a way to quantify Prosodic performance, but I am following
the development of The PRAAT methodology in this area. (Please google this if
you are interested.)

Stage
8... Finding out how A’s eyes were behaving in the new conditions.

This was not quite what I expected. But in retrospect his right eye had been
covered virtually continuously for about 30 minutes! By the end of reading the
text both eyes were starting to work together, this can be seen especially in
the third and fourth line. But there
are still the quite distinctive nystagmus zones when the trigger mechanism is
breaking down.

A series of readings were then done reading monocularly.
From previous experience A was asked to read for a while using only his right eye and the optimal conditions. This is
an attempt to get the ‘brain’used to a new capability.

Left
eye covered, using only his right (Poor?) eye.

The interesting thing here is that with the optimal
background and with no data coming into his left eye, the data being collected
by the right eye was able to enable the control of the movement of his left eye
.

Right
eye covered, using only his left eye.

With his right eye covered, the data being collected by
the left eye, His right eye moved in time with the controlling left eye, although
it did not show the crispest saccades and fixations But the fixation disparity (distance
between the attention points) of the two eyes was more erratic than when it was
the right controlling the left.

Finally
an eyetrace was undertaken binocularly with a small font (10 point) such that
more data was landing in the foveal area of the retina...

The two eyes are now yoked together, but the font
probably too small for the highest quality of fixation.

The graph below shows detail over a 2 second period,
which is typical of the entire graph above. Both eyes show clear yoked saccades
and fixations, but the right eye shows slight fixation instability. But this is
typical of many good readers.

The slight right eye fixation instability most likely would be
solved with a slightly larger font.

We will now wait for a while for A to make use of his
settings in reading/inputting computer activity during which time it is likely (I
think) that there will be a change in the innervations (how many motor end
plates are used in the muscle fibres) and control of the core muscle fibres In
the occulomotor muscles of his right eye, which are responsible for managing
the actual fixations. (This is a new experience for his eye muscles!)

If you are interested in histology and muscle fibre
design I commend you to look at them literature ion this area. Occulomotor muscles are I believe their own
class. They are not cardiac, smooth or skeletal in design. They have a
fascinating histology and physiology of their own; befitting their role in
precise strategic visual data collection.

Wait
for the next thrilling instalment in the control of phonological output by the
visual processing system!

Friday, 22 March 2013

Today we took two colleagues
and put them on the eye tracker using the same text.

One was a ‘self-confessed’
good reader. The other was a self-confessed dyslexic reader. The two eye
traces are below.

The fixations for both took
about the same time, around 280 milliseconds.

The dyslexic colleague, was
processing far fewer characters per fixation than the good reader and the right
eye was being suppressed, although the optician had said that there was no
optical problem with it.

I did then optimise the
screen settings for him. The last graph shows the poor reader reading for the same time period on equivalent text with the same font size.

The reading speed of the dyslexic/poor reader increased from 180 wpm to 418 words per minute.

The non dyslexic colleague was reading at. 474 words per minute on a default setting.

The minimal saccades for the poor reader's eye movements on default would likely give rise to muscle tone build up in the oculo motor muscles reducing eye motility.and reddening of the eyes,

small
effect on reading comprehension. A small-to-moderate
negative effect was found for nonword reading ﬂuency.

Only three of the results were statistically signiﬁcant
(for nonword reading accuracy, word reading accuracy, and letter-sound
knowledge).

Whether results for other outcomes were statistically
signiﬁcant

or not may have depended on the amount of data from which

they were calculated. Overall, the ﬁndings suggest that
teachers

and reading professionals should test poor word readers
for a wide

range of reading skills to determine if they have the
type of poor

reading that responds to phonics.

Implications
for research

The outcomes of this review have at least eight
implications for

research.

First, there is a widely held belief
that phonics training

is the best way to treat poor reading.

Given this belief, we were surprised to ﬁnd that of 6632
records, we found only 11 studies that examined the effect of a relatively pure
phonics training programme in poor readers. While the outcomes of these studies
generally support the belief in phonics, many more randomised controlled trials
(RCTs) are needed before we can be conﬁdent about the strength and extent of
the effects of phonics training perse in English-speaking poor word readers.

Second,
more studies are needed to look at the effects of combining

phonics training with other reading skills. At this early
stage of

research, it would be best to look at the effects of
training phonics

with just one other reading skill. As our understanding
of these

simple effects increases, we can start to look at the
effects of training

phonics with two other reading skills, and so on.

Third, as
mentioned above, this review revealed that phonics training has different
effects on different types of reading skills. Most

of the studies in this review included measures of word
reading

accuracy.

Only one study tested nonword reading ﬂuency and

no study tested letter identiﬁcation. Further, only three
studies

measured letter-sound knowledge, which is surprising
given that

phonics training focuses on letter-sound knowledge.
Future RCTs

of phonics training would do well to include a more
comprehensive range of reading outcomes to understand the true effects of

phonics training on poor word readers.

Fourth,
more research is needed to understand the effect that nonreading moderator
variables –

In this review, we attempted to address these issues via
the subgroup analyses for each outcome. However, only two outcomes

had enough studies to conduct these subgroup analyses.
Thus,

more research is needed on the effects of moderator
variable on

the efﬁcacy of phonics training

Fifth,
the small-to-moderate effect of phonics on phonological

output, which we indexed with phoneme awareness outcome
measures, was interesting because it addressed a controversial issue

regarding the strong relationship between reading and
phoneme

awareness. There is a widespread assumption by many
researchers

and clinicians that poor readers have poor phoneme awareness

because phoneme awareness causes poor reading. However,
there

is good evidence that reading ability affects phoneme
awareness

(Bishop 2004; Castles 2004).

The current review suggests that the effect of reading
ability on phoneme awareness is small-to-moderate in size.

Sixth,
the ’Risk of bias’ analyses in this review revealed that studies of phonics
training on poor readers need to improve the reporting of their methods. While
most studies in this review stated that they used randomised allocation of
participants to groups, few actually described how they generated the
allocation sequence or concealment in their publications, and so we had to ask
for this information personally.

While double-blinding is difﬁcult to guarantee in
cognitive treatment trials, few studies explained how they at least attempted
to instigate double-blinding. Thus, future RCTs of phonics programmes need to
explain the methods of their RCTs in more detail. The CONSORT (Consolidated
Standards of Reporting Trials) 2010 guidelines may prove useful in this respect.

Tuesday, 19 March 2013

Theory and practice. Applying visual processing ideas in a
primary School

Today, my colleague and I begin a short longitudinal study
with a UK Primary school.

Background

All
of the pupils at this school will have followed assiduously the UK government
Phonics programme for the last five years.

This
study will consider what might happen if visual processing is added to the
provision.

The
use of binocular eyetracking technology will allow the consideration of visual
span/perceptual span as a contributor to reading fluency and the quantification
of benefit from optometric /orthoptic intervention and visual parameter
intervention (font size and text background).

The
outcomes will be considered in terms of the role of visual crowding in reading
performance.

Other
posts in this blog look at these issues in adults.

Method

Screen all Year 6 with CRST test ( a comparative rate of
reading test) to indicate eye tracking and visual crowding problems, and a
computerized Oral Fluency Reading (ORF) test, age suited, to attain words per
minute reading speed. Combining the results we will attain a percentile rank of
each child in class, which can be compared to school assessed reading levels.

Both these tests can be undertaken in school by a
Learning Assistant. Each test takes
approx. 1 minute to perform

Select the bottom 20th percentile, plus any
other students who have not been captured in this group but who the school feel
would benefit from further investigation. (A maximum of 9 students for
logistical purposes)

Treatment

For the bottom 20% group in rank order and those identified
as outlined above.

We will run clinic with parents attending if poss. to
perform following:

·Check
for fixation disparity with any reading add found using near mallet unit.
Determine prism as indicated, then check stereopsis and suppression.

·Prescribe
and dispense any reading specific glasses initially
clear.

The above testing
will take approx. 30 mins per student

Stage
2 Optometric provision

In the test group any spectacles required will be provided
and worn for the following tests.

·Re-measure CRST and ORF with specs if
required

·Initial
eye tracking plot on default font/size and white screen.

Stage 3 Computer screen optimisation

·Optimize
font size

·Optimize
colour and luminance

·Repeat
eye tracking with best colour and font.

Stage 4 provision of provision tinted glasses

·Return
any prescription spectacles to lab for precision tinting or dispense plano
spectacles with the precision tint found.

·Supply
tinted specs to child, retest whole
class CRST and ORF in school by Learning Assistant

·Recalculate
and compare percentile class ranking to the original

·A
second pair of spectacles with 50% reduced power and incorrect tint will be
dispensed to all selected students, and CRST and ORF results compared. The Learning
Assistant will not be told which the correct specs were; this would act as a
double blind placebo test.

Thursday, 14 March 2013

Yesterday I wrote that I would be working with adults at
an FE college, who had difficulties with reading. I have been interested for a long time in the
difference between a person who is identified as Dyslexic and a person who may
be dyslexic but has struggled with text
just as much as a person identified as dyslexic but been identified and then in
the UK with a different level of support/intervention.

In Further education colleges, in the UK, there are now
many people undertaking courses to try and improve their employment
opportunities. Many of these are people who have had ‘doing the courses’ as a
condition of their continuing to receive welfare benefits.

No one has ever actually recorded the literacy levels of
this group of people, but improving literacy and numeracy this is a fundamental
component of many of the courses.

The people I am working with attend a very forward
thinking college in the UK. As a component of the course I am advising on
analysing the participants in terms of trying to identify if there are any limiting factors/barriers to their reading performance which can be
lowered or removed easily. This could lead to a step change in their reading
performance.

My contribution is
to identify if there are any correctible visual processing barriers which can be identified. This connects with other posts concerning
whether visual processing is limiting /controlling phonological processing for
any of them and whether the limiting effect can be reduced.

Identification of dyslexia and teaching strategies associated with that is
left to my colleagues at the college. In
an FE college, in the UK, the provision
of funding support from an Additional Learning Support (ALS) fund is not
dependent on a psychological
analysis/labelling process but on the professional assessment of each
individual’s need.

What did I learn?

The three of them were quite different. But before we start I should state that I
could not get the binocular eyetracker to work which substantially restricted
my analysis. I think a connecting
cable needs replacing!

B had had problems at school, a slow reader and writer he
could not keep up when the teacher was writing on the board. Or if he had to copy it down, it was always
wiped off before he could complete it.

B was often told
off for copying from the person sitting next to him. When trying to read by
himself he always got easily distracted and needed to keep his finger on the
page so that he knew where he was when he had been distracted.

He has no problems
concentrating on a computer game or with diagrams. The concentration problems only happen when
he is reading.

In school, when sharing a book, he regularly had to
pretend that he had got to the bottom of the page when the person sharing
with him asked.

‘
Have you finished yet? ‘

‘Can
I turn the page over?’

He simply could not keep up.

When copying words off the board he could never keep up.
The teacher would rub off/wipe the board before he could copy it down.

His writing was slow and very hard for him to read let
alone his teachers

Reading would give him headaches at the front of his head
particularly above his right eye.

His distractibility and slow speed eventually give rise
to behaviour of school avoidance, marginalisation and eventually to persistent
truancy.

He had come back into FE college to do a functional Maths and English course.

.

So the questions to ask are

Is B dyslexic?

How do we help B?

His Tutor at the FE college he attends now had tried all
basic interventions and did not believe he would be diagnosed as dyslexic, I
was told later that he may be identified as Dyspraxic.. My job was to
find out if anything had been missed.

So what was the evidence?

B had been told by
his optician that his vision is perfect. 20/20. He was tested at distance.

With close work there appears to be a convergence
problem. He needs to keep moving the
book/computer away from his eyes to maintain ‘focus’.

This does not
appear to be true when he is gaming with his X-box.

Reading is quite a rigid, iterative process compared with
graphical activity, it appears to put more stress on the muscles of visual
system. Possibly because for a slow reader the sideways moving muscles are only
contracting very short distances at a time, while the other four muscles on
each eye have to keep the eye ‘on the line’ for long time periods. A slow
reader will have to keep these at the same muscle tone for quite long periods.
It must be similar to the effect on your leg muscles of having to walk slowly
with tiny steps on an icy/slippery path. The muscle tone builds up, the joints
and the muscles ache.

Fast. Fluent readers have much greater perceptual spans,
so each saccade is over a comparatively longer distance and changes of line , using the other muscles are
more frequent.

Reading randomly sequenced short words aloud at a default
font size of 12 on a ‘white’ background his RAN score was 81 wpm.( In work in
schools, 80 wpm appears to be a cut off below which the children in the UK are
normally given special needs support.)

Now this test has been used as a measure of phonological
processing speed independent of total reading experience and virtually free of
automaticity issues because of the short simple nature of the words, and no
syntax component. If this was just a
measure of phonological output independent of visual parameters, it should give
the same score as rapid digit naming which statistically appears to be true
with adults we have tested before.

Reading meaningful text with short words and of course
syntax which gives a clue of what the next word should be before you see
it B’s reading speed increased to 128
wpm. The difference here can
be argued as associated with the time /milliseconds, it takes for the
visual system to identify a word being dependent on the probability of a
particular word fitting into the logic/syntax of the preceding word string/
sentence and the mental constructs/ideas inherent in the body of
text/associated graphics being accessed ‘Close’.

Reading complex meaningful text, the same as we use with
dyslexic undergraduates, with many more much longer unfamiliar words and more
complex prosodic components his reading speed was 59wpm. BUT importantly he was able to decode and
blend all the words, it just took longer.

Reading this more complex text the words were longer
approximately 5 characters per word on average compared with 4 characters per
word in the simpler text.

So what the consequence of our meeting?

There was a clear response to changing the font
size. B read a block of randomly
sequenced small words, repeatedly until
he had reached a maximum speed ( this is leaning/familiarisation with
the task.) When he had reached a maximum
speed the font sizes were changed. The
data showed an increased in reading speed until a font size of 25 was reached
after which there was a reduction in speed.

There was no clear relationship between screen background
settings and reading performance.

What did happen though was a consistent gradual reduction
in reading performance over time which masked any other factor.

It seems likely that there is an unresolved problem with
vision at near, a convergence insufficiency which needs dealing with. He is to
go to an optician and be tested at near.

We do not know how the optimal glasses will affect his response to font size but the
present need for a large font may be associated with crowding effects arising
from the problems with binocularity.

I could have checked this by testing him monocularly but
we ran out of time.

This would have also been a way of checking if the
fatigue problems were linked with a convergence problem. Retrospective analysis
is useful when a ‘rematch can be organised. I will have to do that.

………………………………………………………………………

Student
2 (D)

Summary

D has never been
to an optician

There appears to be an severe Astigmatism in her right
eye and both eyes appear to be myopic with presbyopia affecting distance
vision.

She has a problem of bilingualism and phoneme production.
Until 9 years ago she had not read or spoken English.

RDN.. default….
148

RDN font 31…….
193

Benefit
of larger font size…… 30%

Ran aloud default..117

Ran default silent( sub vocalising) ….. 152

Ran font 31 ( sub vocalising) …… 193

ORF default.. 59 aloud
zero silent

ORF opt aloud 82
subvocalising 178.

Benefit……..aloud ….39%

Benefit
..reading/any method…… 202%

Optimal background white optimal font size 31

Lessons learnt

Her native language was Urdu. She started to read English
in 2004. Reading aloud is emabarassing for
her.

At school she always needed to subvocalise and was told
off for reading aloud/mumbling.

The limiting factor appears to be optometric AND font
size. We do not know how much of the font size is a consequence of uncorrected
optometric component.

She is able to decode and blend at her large font but at
small fonts it is not blended as easily. This may be crowding affected by font
size and associated spacing. We will not know that until she has the correct
glasses.

Her left eye has a myopic fixed focus which will make
reading at distance very difficult. Except with her astigmatic right eye. The large optimal font may be associated with
compensation for the uncorrected astigmatism.

If RDN is a measure of phonological processing then
changing the font size has enabled faster phonological processing. There was decoding of the numbers but no
phonics in the sense of decoding and blending. So in the phonological
processing increased by 30%.

If the oral reading fluency is considered , taking away
the psychological worry about correct pronunciation ( sub vocalising) At the default font she could not read by
subvocalising. Aloud this went from 59 wpm to 82 wpm a 39% increase. But since she could now
read subvocally at 178 wpm this meant an effective increase in reading
performance from 59 wpm to 178 wpm. An increase of over 200%
. This may sound extreme but that was the outcome.

D will now go to an optician and get appropriate glasses.
We can then check what her optimal font size is making use of optometric
correction.

………………………………………………………………………..

Student
3 (F)

Summary

Default ( font 16)

ORF….
67 wpm

RAN….92

RDN….
113 ( no crowding effects)

Optimal

ORF
…. 100

Benefit……. 49%

RDN….
128.

Benefit….. 13 %

Optimum Settings

Red

Green

Blue

229

250

250

Font

21

If
we consider that the RDN involved no crowding effects compared with the ORF then perhaps 13 % of the gain in Orf was
associated with crowding. The rest of
the gain in ORF may have been associated with increased processing speed not
linked to crowding.

F
was able to read all of the texts offered but slowly. The normal sample text
used with dyslexic undergraduates was used.

Student F responded to font size, as can be seen in the
graph below.

He also responded to changes in the background setting. But he
only needed a very subtle change from white. To him the difference was immense.
We needed to reduce the brightness of the red pixels but only by about 10%. All
of the filters available commercially would have removed too much red or
green and blue as well. As such when
offered them in a forced choice, or casual process, all of them would have been
worse than white. The outcome of course
would have been a false negative.

F has now been diagnosed as dyslexic, it will be
interesting to watch what happens to his reading performance as the support
clicks in.